Heterocyclic thiadiazolylureas

ABSTRACT

This invention discloses new compounds of the formula   wherein R1 is selected from the group consisting of alkyl, alkenyl, haloalkyl, cycloalkyl, alkoxy, alkylthio, alkylsulfonyl and alkylsulfinyl; Z1 and Z2 are independently selected from the group consisting of oxygen and sulfur; R2, R3, R4, R5, R6 and R7 are each selected from the group consisting of hydrogen and alkyl, m is an integer from 0 to 2, and n is the integer 1 or 2. The compounds of the the above description are useful as herbicides.

United States Patent [1 1 Krenzer Aug. 26, 1975 l HETEROCYCLIC THIADIAZOLYLUREAS [75] Inventor: John Krenzer, Oak Park, Ill.

[73] Assignee: Velsicol Chemical Corporation,

Chicago, Ill.

[22] Filed: Aug. 9, 1973 [2|] Appl. No.: 387,05]

52 us CI 260/3068 o; 71/90; 260/327 0,

260/327 M; 260/338; 260/3407; 260/3409 1511 .Int. Cl C07d 91/62 581 Field of Search 260/3()6.8 D

[56] References Cited UNITED STATES PATENTS 9/1973 Krcnzer n 260/3068 D l/l974 Krenzcr Zoo/306.8 D

Primary Exuminer-Richard J. Gallagher Attorney, Agent, or FirmRobert J Schwarz; Dietmar Hx Olesch [5 7] ABSTRACT This invention discloses new compounds of the formula 6 Claims, No Drawings HETEROCYCLIC THIADIAZOLYLUREAS This invention relates to new compositions of matter and more specifically relates to new chemical compounds of the formula wherein R is selected from the group consisting of alkyl. alkenyl. haloalkyl. cyeloalkyl. alkoxy. alkylthio. alkylsulfonyl and alkylsulfinyl; Z and Z are independently selected from the group consistof oxygen and sulfur; R. R. R. R. R". and R are each selected from the group consisting of hydrogen and alkyl; m is an integer from O to 2: and n is the integer l or 2. The compounds of this invention are unexpectedly useful as herbicides.

In a preferred embodiment of the present invention R is selected from the group consisting of lower alkyl. lower alkenyl. lower chloroalkyl. lower bromoalkyl. trifluoromethyl. cycloalkyl of from 3 to 7 carbon atoms. lower alkoxy. lower alkylthio. lower alkylsulfonyl. and lower alkylsulfinyl; and R. R". R. R. R. and R are each selected from the group consisting of hydrogen and lower alkyl. The term lower as used herein designates a straight or branched carbon chain of up to 6 carbon atoms.

The compounds of the present invention wherein R is hydrogen can be prepared by reacting a thiadiazolyl isocyanate dimer of the formula N N II II llli (llll wherein R. R. R". R. R Z. 2*. n and m are as heretofore described. This reaction can be effected by add ing the isocyanate dimer of formula II to a solution of the compound of formula III in an organic solvent such as benzene at room temperature with stirring. The reaction mixture can then be heated on a steam bath for a period of from about 5 to 60 minutes to ensure com letion of the reaction. After this time the reaction mixture can be stripped of solvent under reduced pressure to yield the desired product as a residue. This product can be used as such or can be further pruified by conventional means.

The isocyanate dimer of formula ll can be prepared by reacting an aminothiadiazole of the formula wherein R is as heretofore described. with phosgene. This reaction can be effected by adding a solution of phosgene in ethyl acetate to a solution or suspension of the aminothiadiazole in ethyl acetate at room tempera-' ture with stirring. After the addition is completed stirring can be continued for a period of up to about 18 hours to ensure completion of the reaction. The reaction mixture can then be purged with nitrogen to remove unreactcd phosgene. The desired product can then be recovered by filtration if it forms as a precipitate or upon evaporation of the solvents used if soluble therein.

The compounds of formula [II can be prepared by reacting a compound of the formula wherein X is chlorine or bromine and Z. Z. R. R". R". R and m are as heretofore described with an amine of the formula wherein R is as heretofore described. This reaction can be effected by adding the compound of formula V to a solution of the amine in a suitable solvent such as water or methanol. The mixture can then be stirred for a period of up to about l8 hours. After this time base such as sodium hydroxide is incrementally added and stirring is continued for an additional period of up to l8 hours; the desired product can then be recovered upon decantation of the organic phase if water is used as a solvent or upon evaporation of the solvent if an organic solvent is used. The resulting product can then be purified by conventional means.

The compounds of formula V can be prepared by reacting an aeetal of the formula wherein X and n are as heretofore described. with a diol or dithiol of the formula (Vlli) therein R. R". R. R Z Z and m are as heretofore leseribcd. This reaction can be effected by combining he compound of formula VII with the compound of ormula VII] in about equimolar amounts and in the presence of an acid catalyst. such as sulfuric acid or tolene sulfonic acid. under anhydrous conditions. The nixturc can be heated at reflux for a period of from lbOUt l to about 4 hours. After this time the reaction nixture can be distilled under reduced pressure to yield he desired product Exemplary diols and dithiols of formula Vlll useful or preparing the compounds of formula V are ethandi- )l-l.2. propandiol-1 2, propandiol-l.3. butandiol-l.2, iutandiol-LB butandiol-l,4, butandiol-2,3. pentandi- :l-l 2, pentandiol-LB, pentandioHA, pentandiol-2.3. mentandiol-ZA, 2-methylpentandiol-2A. 2- nethylpropadioll .2. 2-methylbutandiol-2.3. 3-methyl- )utandiol-l ,3. hexandiol-LZ hexandiol-l,4. hexandiol- 2,3, hcxandiol-ZA, hexandiol-2.5. hexandiol-3.4, 5-methylhexandiol-3 4 3ethylhcxandiol-3A, ethandihiol-LZ. propandithiol-LZ, propandithiol-l,3, butaniithiol-LZ, butandithioll .3, butandithiol-l.4, butandihim-2.3. pentadithiol-l .2. and the like.

Exemplary thiadiazoles of formula IV are 2-amino-5- nethyl-l .3.4-thiadiazole. Z-amino-S-isopropyl-l 3.4- .hiadiazole. Z-aminoS-t-buIyl-I,3.4-thiadiazole. 2- imino-fi-hcxyl-l ,BA-thiadiazole, 2-amino5-a|lyl-l .3,4- .hiadiazole, 2-amino-5-hex-4-enyll ,3,4-thiadiazole. Z-amino-S-chloromcthyl-1,3,4-thiadiazole. 2'amino5- )romomcthyll .3 ,4-thiadiazole. 2-amino-5-tri- :hloromethyl-l .3,4-thiadiazole. 2-amino5-tri- 1uoromcthyll ,3.4-thiadiazole, Z-amino-S-B-bromo- :thyll ,3 4-thiadiazolc. Z-amino-S-y-chlopropyll 3.4- :hiadiazolc, Z-amino-S-cyclopropyll ,3.4-thiadiazole. 2-amino-5-cyclobutyl-l .3,4-thiadiazolc 2-amino-5- :yelopentyl-l,3.4-thiadiazole. Z-amino-S-cyclohexyl- 1,3.4-thiadiazole, Z-amino-S-cycloheptyll .3.4- :hiadiazole, Z-amino-S-methoxy-1.3,4-thiadiazole. 2- .imino-fi-ethoxy l .3.4-thiadiazole. 2-amino-5-propoxyl .3.4-thiadiazole. Z-amino-S-butoxy- ,3,4-thiadiazole, Z-amino-S-hcxyloxyl .3.4thiadiazole, 2-amino-5- rriethylthiol .3 .4-thiadiazole. Z-amino-S-ethylthio- 1.3 .4-thiadiazolc. Z-amino-S-butylthiol ,3,4- thiadiazole, Z-amino-S-hexylthio-l 3.4-thiadiazole, 2- amino-S-methylsulfonyl-l 3,4-thiadiazole 2-amino-5- :thylsulfonyll .3.4-thiadiazolc. Z-amino-S-propylsulfonyl-l .3.4-thiadiazole. 2-amino-S-pentylsulfonyl-l .3 4- thiadiazolc. 2-amino-S-hcxylsulfonyll ,3.4-thiadiazolc.

Z-arnino-S-mcthylsulfinyl-1.3,4thiadiazole. Zamino-S- ethylsulfinyl-l .3.4-thiadiazole, Z-amino-S-propylsulfinyl-l ,3,4-thiadiazolc Z-amino-S-butylsulfinyll ,3.4- thiadiazole. Z-amino-S-hexylsulfinyll .BA-thiadiazole. Z-methylaminoS -trifluoromethyll .BA-thiadiazole.

the like.

The compounds of this invention wherein R is alkyl can be prepared by reacting a compound of formula III with a carbamoyl chloride of the formula wherein R is alkyl and R is as heretofore described. This reaction can be effected by combining about equimolar amounts of the compounds of formula III and IX in an inert organic reaction medium such as benzene and in the presence of an acid acceptor such as a tertiary amine or alkali metal carbonate or bicarbonate. The reaction mixture can be heated at temperatures of up to the reflux temperature of the mixture to ensure completion of the reaction. After this time the mixture is filtered to remove acid acceptor salts and the filtrate is stripped of solvent to yield the desired product. This product can be used as such or can be further purified by conventional means.

The compounds of formula lX can be prepared by reacting a compound of the formula N N ll ll wherein R is alkyl and R' is as heretofore described, with phosgene. This reaction can be effected by adding the thiadiazole of formula X to a solution of phosgene in an inert solvent such as benzene and thereafter heating the resulting mixture at reflux with stirring for a period of several hours until the reaction mixture becomes clear. After this time the mixture can be stripped of solvent to yield the desired product as the residue.

Suitable thiadiazoles of formula X useful for preparing the compounds of this invention are the ememplifled thiadiazoles of formula IV which have in place of the 2-amino substituent an Z-mcthylamino, 2- ethylamino, Z-propylamino. 2-butylamino. 2- pentylamino or 2-hexylamino substituents. The manner in which the compounds of the present invention can be prepared is more specifically illustrated in the following examples.

EXAMPLE 1 Preparation of Z-trifluoromethyll ,3.4-thiadiazol-5-yl isocyanate dimer A saturated solution of phosgene in ethyl acetate ml) was charged into a glass reaction vessel equipped with a mechanical stirrer. A slurry of 2- trifluoromcthyl-S-amino-l.3,4-thiadiazole (45 grams) in ethyl acetate (300 ml) was added to the reaction vessel and the resulting mixture was stirred for a period of about lb hours resulting in the formation of a precipitate. The reaction mixture was then purged with nitrogen gas to remove unreacted phosgenc. The purged mixture was filtered to recover 48 grams of a white solid. This solid was recrystallized from dimethyl formanide to yield the desired product 2trifluoromethyl- 1,3.4-thiadiazol-5-yl isocyanate dimer.

EXAMPLE 2 Preparation of l-hromomethyll .3-dioxolane The dimethyl acctal of Z-bromoacetaldehydc (290 grams) and ethandioll .2 (92 grams) were charged into a glass reaction vessel equipped with a mechanical stirrer, thermometer and reflux condenser. Hydrochloric acid 1.5 ml) was added to the flask and the reaction mixture was refluxed for a period of about 2 hours. After this time the reaction mixture was distilled under reduced pressure to yield the desired product 2-bromoinethyll .3-dioxolane.

EXAMPLE3 Preparation of N-( l,3-Dioxolan-2-ylmcthyl )-N-methylaminc A 40% by weight aqueous solution I ml) of me thylamine and Z-bromomethyl-l.3-dioxolane (40 grams) were charged into a glass reaction vessel equipped with a mechanical stirrer. The reaction mixture was stirred for a period of about l8 hours. After this time sodium hydroxide l8 grams) was added with stirring over a period of about 4 hours. Stirring was then continued fof an additional period of about 16 hours. The organic phase of the reaction mixture was then separated. was washed with aqueous potassium carbonate and dried over anhydrous magnesium sulfate. The dried product was then distilled under rcduccd pressure to yield the desired product N-(1.3- dioxolan-LylmethylJ-N-methylamine.

EXAMPLE 4 Preparation of N-( Z-Trifluoromethyl-l .3.4-thiadiazol-5-yl N l.3-dioxolan-Z-ylmethyl )-N '-methylurea Z-Trifluormethyll ,3 4-thiadiazol-S-yl isocyanate dimer (3.l grams) was added to a solution of N-( 1.3- dioxolan-2 ylmethyl) N-methylaminc (2 grams) in benzene (l0 ml) contained in a glass reaction vessel equipped with a mechanical stirrer and thermometer. The mixture was heated on a steam bath for a period of about 1 hour. The mixture was then stripped of solvent under reduced pressure to yield a solid residue. The residue was recrystallized from an ether pentane mixture to yield the desired product N-(2- trifluoromethyll ,3,4-thiadiazol-5-yl )N l.3- dioxolan-Z-ylmethyl)-N'-methylurea having a melting point of 1 14 to H5 C.

EXAMPLE 5 Preparation of Z-Chloromethyl-1.3-dioxolanc The dimethyl acetal of Z-chloroacetaldehydc (125 grams: 1.0 mole) and ethandiol-l ,2 (62 grams; 1.0 mole) are charged into a glass reaction flask equipped with a mechanical stirrer. thermometer and reflux condenser. Toluene sulfonic acid (0.3 grams) is added to the flask and the reaction mixture is refluxed for a period of about 2 hours. After this time the reaction mixture is distilled under aspirator partial pressure to remove methanol. yielding the desired product Z-chloromethyll .3-dioxolane.

EXAMPLEo Preparation of N( l.3-Dioxolan-2-ylmethyl )-N-cthylamine A 40% by weight aqueous solution of ethylamine (100 ml) and Z-chloromethyl-l .3-dioxolane (35 grams) are charged into a glass reaction vessel equipped with a mechanical stirrer. The reaction mixture is stirred fora period of about l8 hours. After this time sodium hydroxide (18 grams) is added with stirring over a period of about 4 hours. Stirring is then continued for an additional period of about 16 hours. The organic phase of the reaction mixture is then separated, washed with aqueous potassium carbonate and dried over anhydrous magnesium sulfate. The dried product is then distilled under reduced pressure to yield the desired product N-( l.3-dioxolanc2-ylmethyl)-N- ethylamine.

EXAMPLE 7 Preparation of 'l-LButyll ,3.4-thiadiazol5-yl Isocyanate Dimer A saturated solution of phosgene in ethyl acetate lUU ml) was charged into a glass reaction vessel equipped with a mechanical stirrer. A slurry of 2-tbutyl-S-amino-l.3.4-thiadiazolc 10 grams) in ethyl ac etatc (300 ml) was added to the reaction vessel and the resulting mixture was stirred for a period of about 16 hours resulting in the formation of a precipitate. The reaction mixture was then purged with nitrogen gas to remove unreacted phosgene. The purged mixture was then filtered to recover the desired product Z-t-butyll,3.4-thiadiazol-5yl isocyanate dimer.

EXAMPLE 8 Preparation of N-( Z-t-Butyll .3 .4-thiadiazol-5-yl )-N l.3-dioxolan 2- ylmcthyl )-N -ethylurea 2-t-Butyl-l,3,4-thiadiazol-5-yl isocyanatc dimer (3 grams) abd a solution of N-( l,3-dioxolan-2-ylmethyl)- N-cthylamine (2 grams) in benzene 10 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The mixture is warmed on a steam bath with stirring for a period of about 1 hour. After this time the mixture is stripped of solvent under reduced pressure to yield a solid residue. The residue is recrystallized to yield the desired product N-( Z-t-butyll 3.4-thiadiazol-5-yl N'-( l,3- dioxolan-Z-ylmethyl )-N'-ethylurea.

EXAMPLE 9 Preparation of 2-Chl0romethyll ,3-dithiepane The dimethyl acetal of Z-chloroacetaldehydc grams. 1.0 mole) and butandithiol-IA (122 grams, 1.0 mole) are charged into a glass reaction vessel equipped with a mechanical stirrer. thermometer and reflux condenser. Toluene sulfonic acid (0.3 grams) is added to the reaction mixture and the mixture is refluxed for a period of about 2 hours. After this time the reaction mixture is distilled under aspirator pressure to yield the desired product Z-chloromethyld .B-dithiepane.

EXAMPLE l0 Preparation of N-( l.lDithiepan-Z-ylmethyl )-N-methylamine A 40% by weight aqueous solution of methylaminc l00 ml) and Z-chloromethyld .3-dithiepan (50 grams, are charged into a glass reaction vessel equipped witr a mechanical stirrer. The reaction mixture is stirred l'oi a period of about l8 hours. After this time sodium hydroxide 18 grams) is added with stirring over a periot of about 3 hours. Stirring is then continued for an additional period of about 16 hours. The organic phase oi the reaction mixture is then separated. is washed witl' aqueous potassium carbonate and dried over anhyrous magnesium sulfate, The dried product is then dislled under reduced pressure to yield the desired prod- :t N-( l .3-dithiepan-2-ylmethyl )-N-methylamine.

EXAMPLE 1] Preparation of N-( 2-Methylthiol .3,4-thiadiazol-5-yl l-N- methylcarbamoyl chloride Z-methylthio-S-methylaminol ,3.4.-thiadiazole (0.1

role) and a solution of phosgene 1 mole) in benane (200 ml) are charged into a glass reaction vessel quipped with a mechanical stirrer and reflux conenser. The reaction mixture is heated at reflux for a eriod of about 4 hours. After this time the reaction iixture is stripped of benzene and unreacted phosgene yield the desired product N-(2-methylthio-l,3 4- tiadiazol-S-yl )-N-methyl-carbamoyl chloride.

EXA MPLE l 2 Preparation of N-( 2-Methylthio-l .3.4-thiadiazol-5-yl )-N-methyl-N methyl-N'-( l ,3-dithiepan-2-yl )urea N-( 2-methylthiol .3 .4-thiadiazol-5-yl )-N- iethylearbamoyl chloride (0.05 mole), N-( 1.3- ithiepan-Z-ylmethyll-N-methylamine (0.05 mole), tri thylamine (0.07 mole) and benzene (200 ml) are harged into a glass reaction vessel equipped with a iechanical stirrer. thermometer and reflux condenser. he reaction mixture is then heated at reflux for a per- .id of about 5 hours. After this time the mixture is ooled to room temperature and is filtered. The filtrate washed with water and dried over anhydrous magneium sulfate. The dried solution is then stripped of henene under reduced pressure to yield the desired prodlet N-( Z-methylthiol .3,4-thiadiazol-5-yl )-N-methyl- -l'-methyl-N'-( l .3'dithiepan-2-yl)urea.

EXAMPLE 13 Preparation of Z-Chloromcthyll .3-dioxane The dimethyl acetal of 2-chloroacetaldehyde (l grams; 1.0 mole). and propandio]-l.3 (76 grams 1.0 nole) are charged into a glass reaction vessel equipped vith a mechanical stirrer. thermometer and reflux con lenser. Toluene sulfonic acid (0.3 grams) is added to he reaction mixture and the mixture is refluxed for a )eriod of about 3 hours. After this time the reaction nixturc is distilled under aspirator pressure to yield the iesired product 2-chloromethyl-l ,3-dioxane.

EXAMPLE 14 Preparation of N-( l .3-Dioxan-ylmethyl)amine Cooled Lchloromethyl-l.3-dioxane (0.2 mole)dis- ;olved in absolute alcohol 150 ml) and liquid ammoiia (2.0 mole) are charged into a pressure vessel. The ressel is sealed and heated to a temperature of about l20 C. with shaking for a period of about 12 hoursv The pressure vessel is cooled and the ammonia is alowed to escape. The reaction mixture is then com- Jined with absolute ethanol l l50 ml) and the resulting solution is filtered. The filtrate is stripped of alcohol lad is dissolved in ether. The ether solution is filtered to remove inorganic salt. The filtered solution is stripped of ether on a steam hath under reduced pres sure to yield the desired product N-( l 3-dioxan-Z- ylmcthyljamine.

EXAMPLE 15 Preparation of N-( Z-Methylsulfonyll .BA-thiadiazol-S-yl l-N- methylearbamoyl chloride Z-methylsulfonyl-5-methylcarbamoyl chloride 2-methylsulf'onyl-5-methylaminol ,3 ,4-thiadiazole (0.1 mole) and a solution of phosgene (0.11 mole) in benzene (200 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer and reflux eondenser. The reaction mixture is heated at reflux for a period of about 4 hours. After this time the mixture is stripped of benzene and unreacted phosgene to yield the desired product N-(2-methylsulfonyl-l.3,4-

thiadiazol-S-yl )-N-methylcarbamoyl chloride.

EXAMPLE [6 Preparation of N-( Z-Methylsulfonyll ,3 ,4-thiadiazol-5-yl )-N-methyl- N'-( l,3-dioxan-2-ylmethyl )urea N-( 2-Methylsulfonyll ,3.4-thiadiazol-5-yl )-N- methylcarbamoyl chloride (0.05 mole). N-( 1.3-dioxan- Z-yImethylJamine (0.05 mole). triethylamine (0.07 mole) and benzene (200 ml) are charged into a glass reaction vessel equipped with a mechanical stirrer. thermometer and reflux condenser. The reaction mixture is then heated at reflux for a period of about 4 hours. After this time the mixture is cooled to room temperature and is filtered. The filtrate is washed with water and is dried over anhydrous magnesium sulphate. The dried solution is then stripped of solvent under reduced pressure to yield the desired product N-( 2- methylsulfonyll .3,4-thiadiazol-5-yl J-N-methyl-N l.3-dioxan-2-ylmethyl)urea.

Additional compounds within the scope of the present invention can be prepared by the procedures de tailed in the foregoing examples. In the following examples are given the essential starting materials to prepare the indicated named compounds by the methods heretofore described.

EXAMPLE 17 The dimethyl acetal of 2-chloroacetaldehyde propandiol ll ammonia +2-isopropyl-S-ethylaminol,3.4-thiadiazole phosgene N(2 isopropyl-l,3 4- thiadiazol-S-yl )-N-ethyl-N 4-mcthyl-l ,3-dioxolan-2- ylmethyl)urea.

EXAMPLE l8 The dimethyl acetal of 3-chloropropionaldehyde butandiol-l.4lmethylamine +2-mcthyloxy-5-amino- 1,3.4-thiadiazole phosgene N-(2-methoxyll .3.4- thiadiazol-S-yl)-N'-( l.S-dioxcpan-Z-ylethyl)-N- methylurea.

EXAMPLE 19 The dimethyl acetal of Z-chloroacetaldehye butandiol-l .2 propylaniine 'l-cyclohexyhfiamino-1.3.4- thiadiazole phosgene N-(Z-eyclohexyl-l3.4- thiadia1ol-5-yl )-T J 4-eth l l .3-dioxolan-3-ylmethyl N'propylurea.

EXAMPLE 20 The dimethyl acetal of Z-chloroacetaldehye cthandithiol methyl-amine 2-allyl-iethylaminol.3.-l-thiadia/,ole pliosgene N-l:*C}'Cl\ll\CXl-l.3.-1-

thiadiazol-S-yl )-N 4-cthyll .3-dioxolan-S-yImethyl N-propylurea.

EXAMPLE 21 The dimethyl acetal of Z-chloroacetaldehyde propandithioLl .3 methylamine Z-methylsulfinyl-S- propylamino-l.3.4-thiadiazol phosgcne N-(Z- methylsulfinyl-l.3.4-thiadiazol-5-yl)-N-propyl-N'-( l.3- dithian-Z-ylmethyl J-N'-methylurea.

N'-( l .3-tlioxolan-lylmethyl)-N'-methylurea. N( 2- tribromomethyl-l.3.4-thiadiazol-5-yl)-N'-(1.3- dioxolan-Z-ylmethyl )-N'-methylurea. N-[ 28 10 methylurea. N-(2-butylsulfinyll.3.4-thiadiazol-5yl)- N'-( l.3-dioxan-2-ylmethyl)-N'-methylurca. N42 hcxylsultinyll .3,4-thiadiazol-5-yl )-N'-( l.3-di0xan-2- ylmethyl )-N'-methylurea. N-( Z-t-butyll 3.4- thiadiazol-S-yl )-N-methyl-N 4-propyll,3-dioxepan- 2-ylmethyl )-N '-methylurea. N-(2-t-butyl-1.3 4- thiadiazol-S-yl )-N-propyl-N 4-butyll .3-di0Xepan-2- ylmethyl )-N '-methylurea. N-( 2-t-butyll .3.4- thiadiazo]-5 yl)-Nbutyl-N-(4-pentyl-1,3-dioxepan-2- ylmethyl )-N'-methylurea, N-( Z-t-butyl-l .3.4- thiadiazol-S-yl )-N-pentyl-N'-(4-hexyl-l .3-dioxepan-2- ylmethyl )-N"methylurea, N-( Z-t-butyl- 1 .3.4- thiadiazol-S-yl)-N'hexy-N'-(4.5 -dimethyl-l.3- dioxolan-2-ylmethyl)-N'-methylurea, N-(2-t-butyll .3.4-thiadiazol-5-yl )-N'-(4.5-diethyl-l .3-diox0lan-2- ylmethyl )-N'-methylurea. N-( Z-t-butyll .3 .4- thiadiazol-S-yl )-N'-( 4.5-dipropyl-l .3-dioxolan-2- ylmethyl )-N'-methylurea. N-( 2-t-butyl' l .3 .4- thiadiaz0l5-yl)-N'-(4.5-dihexyl-l.3-dioxolan-2- ylmethyl )-N'-methylurea. N-( 2-t-butyl- I .3 .4- thiadiazol-S-yl )-N'-methylurea. N-( 2-t-butyll .3.4- thiadiazol-S-yl )-N'-( 4.7-dibutyll .3-dioxepan-2- ylmethyl )-N-methylurea. N-( 2-t-butyll .3.4- thiadiazol-S-yl)-N'-(4.7-dihcxyl-l.3-dioxepan-2- ylmethyl)-N'-methylurea.

For practical use as herbicides the compounds of this invention are generally incorporated into herbicidal compositions which comprise an inert carrier and a herbicidally toxic amount of such a compounds. Such herbicidal compositions, which can also be called for mulations. enable the active compounds to be applied conveniently to the site of the weed infestation in any desired quantity. These compositions can be solids such as dusts. granules or wettable powders; or they can be liquids such as solutions. aerosols. or emulsifi able concentrates.

For example, dusts can be prepared by grinding and blending the active compounds with a solid inert carrier such as the tales. clays. silieas, pyrophyllite. and the like. Granular formulations can be prepared by impregnating the compound. usually dissolved in a suitable solvent. onto and into granulated carriers such as the attapulgites or the vermiculitcs. usually of the particle size range of from about 0.3 to l.5 mm. Wettable powdcrs. which can be dispersed in water or oil to any desired concentration of the active compound. can be prepared by incorporating wetting agents into concentrated dust compositions.

In some cases the active compounds are sufficiently soluble in common organic solvents such as kerosene or xylene so that they can be used directly as solutions in these solvents. Frequently. solutions of herbicides can be dispersed under super-atmospheric pressure as aerosols. However. preferred liquid herbicidal compositions are emulsifiable concentrates. which comprise an active compound according to this invention and as the inert carrier, a solvent and an emulsifier. Such emulsifiable concentrates can be extended with water and or oil to any desired concentration of active compound for application as sprays to the site of the weed infestation. The emulsifiers most commonly used in these concentrates are nonionie or mixtures of non ionic with anionic surfacc-active agents. With the use of some emulsifier systems an inverted emulsion (water in oil) can be prepared for direct application to weed infestations.

A typical herbicidal composition according to this .nvention is illustrated by the following example, in which the quantities are in parts by weight.

EXAMPLE 23 Preparation of a Dust Product of Example 4 Powdered Talc The above ingreedients are mixed in a mechanical grindcrblender and are ground until a homogeneous, free-flowing dust of the desired particle size is obtained. This dust is suitable for direct application to the site of the weed infestation.

The compounds of this invention can be applied as herbicides in any manner recognized by the art. One method for the control of weeds comprises contacting the locus of said weeds with a herbicidal composition comprising an inert carrier and as an essential active ingredient, in a quantity which is herbicidally toxic to said weeds, a compound of the present invention. The concentration of the new eompouds of this invention. The concentration of the new compounds of this invention in the herbicidal compositions will vary greatly with the type of formulation and the purpose for which it is designed, but generally the herbicidal compositions will comprise from about 0.05 to about 95 percent by weight of the active compounds of this invention. in a preferred embodiment of this invention. the herbicidal compositions will comprise from about 5 to about 75 percent by weight of the active compound. The compositions can also comprise such additional substances as other pesticides. such as insecticides, nematocides, fungicides, and the like; stabilizer. spreaders, deactivators, adhesives, stickers, fertilizers, activators, synergists, and the like.

The compounds of the present invention are also useful when combined with other herbidies and/or defoliants, dessicants, growth inhibitors, and the like in the herbicital compositions heretofore described. These other materials can comprise from about 5 to about 95% of the active ingredients in the herbicidal compositions. Use of combinations of these other herbicides and/or defoliants, dessicants, etc., with the compounds of the present invention provide herbicidal compositions which are more effective in controlling weeds and often provide results unattainable with separate compositions of the individual herbicides. The other herbi cides, defoliants, dessicants and plant growth inhibitors, with which the compounds of this invention can be used in the herbicidal compositions to control weeds, can include chlorophenoxy herbicides such as 2,4 D, 2,4,5-T, MCPA, MCPB, 4(2,4-DB). 2,4-DEB, 4-CPB, 4-CPA, 4-CPP, 2.4,5-TB, 2,4,5TES, 3.4-DA. silvex and the like; carbamate herbicides such as IPC, CIPC, swep, barban, BCPC, CEPC, CPPC, and the like; thiocarbamate and dithiocarbamate herbicides such as CDEC, metham sodium, EPTC, diallate. PECB. perbulate, vernolate and the like; substituted urea herbicidcs such as norea, siduron, dichloral urea, cloroxuron, cycluron, fenuron. monuron. monuron TCA, diuron, linuron, monolinuron. neburon. buturon, trimeturon and the like; symmetrical triazinc herbicides such as simazine. chlorazine, atraone, dcsmetryne, norazine. ipaYinc, prometryn, atrazine. and the like; chloroacetahi l mide herbicides such as alpha-chloro-N, N-dimethylacetamide, (DE/ i, CDAA, alpha-chloro-N- isopropylacetamide. 2-chloro-N-isopropylaeetanilide, J-(chloroacetyl)morpholine, B-(chloroaeetyl) piperidine, and the like; chlorinated aliphatic acid herbicides such as TGA, dalapon, 2,3di-chloropropionic acid, 2,2,3-TPA and the like; chlorinated benzoic acid and phenylaeetic acid herbicides such as 2,3,6-TBA, 2,3,5,6-TBA, dicamba, tricamba, amiben, fenac, PBA, 2-methoxy-3,o.-dichlorophenylacetic acid, 3-methoxy 2,o-dichlorophenylacetic acid, 2methoxy3,5,6-trichloro-phenylacctic acid, 2,4-dichloro-3-nitrobenzoie acid and the like; and such compounds aminotriazolc, maleic hydrazide, phenyl mercuric acetate, endothal, biuret, technical chlordane, dimethyl 2,35,6- tetrachloroterephthalate, diquat, erbon, DNC, DNBP, dicblobenil, DPA, diphenamid, dipropalin, trifluralin, solan, dicryl, merphos, DMPA, DSMA, MSMA, potassium azide, acrolein, bencfin, bensulide, AMS, bromacil, 2-( 3,4-dichlorophenyl J-4-methyll ,2,4- oxadiaZolidine-3,S-dione, bromoxynil, cacodylic acid, CMA, CPMF, cypromid, DCB, DCPA, dichlone, diphenatril, DMTT, DNAP, EBEP, EXD, HAC, ioxynil, IPX, isocil, potassium eyanate, MAA, MAMA, MCPES, MCPP, MH, molinate, NPA, OCH, paraquat, PCP, picloram, DPA, PCA, pyrichlor, sesone, terbacil, terbutol, TCBA, brominil, CP-5Ul44, H-l76-l, H-732. M-2901, planavin, sodium tetraborate, calcium cyanamid, DEF, ethyl xanthogen difulfide, sindone, sindome B, propanil and the like.

Such herbicides can also be used in the methods and compositions of this invention in the form of their salts, esters, amides, and other derivatives whenever applicable to the particular parent compounds.

Weeds are undesirable plants growing where they are not wanted, having no economic value, and interfering with the production of cultivated crops, with the growing of ornamental plants, or with the welfare of livesstock. Many types of weeds are known, including annuals such as pigweed, lambsquarters, foxtail, crabgrass, wild mustard, field pennycress, ryegrass, goose-grass, chiekweed, wild oats, velvet leaf, purselane, barnyard grass, smartweed, knotwecd, cocklebur, wild buckwheat, kochia, medic, corn Cockle, ragweed, sowthistle, coffee-weed, croton, cuphea, dodder, fumitory, groundsel, hemp nettle, knowel, spurge, spurry, emex, jungle rice, pondweed, dog fennel, carpetweed, morning glory, bedstraw, ducksalad and naiad; biennials such as wild carrot, rnatriearia, wild barley, campion, chamomile, burdock, mullein, round-leaved mallow, bull thistle, hounds-tongue, moth mullein, and purple star thistle; or perennial rye-grass, quackgrass, Johnson grass, Canada thistle, hedge bindwecd, Bermuda grass, sheep sorrel, curly dock, nutgrass, field chiekweed, dandelion, eampanula. lield bindweed, Russian knapweed, mesquite. toadflax, yarrow, aster, gromwell, horsetail, ironwecd, sesbania, bulrush, cattail and winter-crcss,

Similarly, such weeds can be classified as broadlcaf or grassy weeds. It is economically desirable to control the growth of such weeds without damaging beneficial plants or livestock.

The new compounds of this invention are particularly valuable for weed control because they are to\ic to many species and groups of needs while they are relatively non-tmtic to may benficial plants, The exact amount of compound required ill depend on a \ariety of factors. including the hardiness of the particular weed species. weather. type of soil, method of application. the kind of beneficial plants in the same area. and the like. Thus. while the application of up to only about I or 2 ounces of active compound per acre may be sufficient for good control of a light infestation of weeds growing under adverse conditions. the application of ten pounds or more of active compound per acre may be required for good control of a dense infestation of hardy perennial weeds growing under favorable conditions.

The herbicidal toxicity of the new compounds of this invention was demonstrated by experiments carried out for the pre-emergence control of a variety of weeds. In these experiments small plastic greenhouse pots were filled with dry soil were seeded with the various weed seeds. Twenty four hours or less after seeding the pots were sprayed with water until the soil was wet and the product of Example 4 formulated as aqueous emulsions of acetone solutions containing emulsifiers were sprayed at a rate of 20 pounds per acre on the surface of the soil.

After spraying. the soil containers were placed in the greenhouse and provided with supplementary heat as required and daily or more frequent watering. The plants were maintained under these conditions for a period of 27 days. 21 and 27 days after treatment the condition of the plants and the degree of injury to the plants was rated on a scale of O to It). as follows: (J no injury. 1.2 =slight injury. 3.4 moderate injury. 5.6 moderately severe injury. 7.8.9 severe injury and death. The herbicidal effectiveness is demonstrated by the following data in Table l.

The herbicidal activity of the compounds of this invention was also demonstrated oy experiments carried out for the post-emergence control of a variety of weeds. ln these experiments the product of Example 4 was formulated as aqueous emulsions and sprayed at a rate of ll) pounds per acre on the foliage of the weed species that have attained a prescribed size. After spraying the plants were placed in a greenhouse and watered daily or more frequently. Water was not applied to the foliage of the treated plants. The severity of the injury was determined and 27 days after treatment and was rated on the scale offrom to 10 heretofore described. The effectiveness as a post emergence herbicide is demonstrated by the data in Table I.

TABLE I INJLRY RAT ING Pre-Fmergence Post-Hnergence Weed Species 21 days 27 days l5 days 27 days Yellow Nutsedgc 4 3 8 9 Wild Oates to to lll .limsonweed lll I(l Hi It) Yel etleaf HI It! A .lohnsongrass h 9 ll) 9 Pigweed 7 J l() ltl Mustard lt) ll) lll ll) Yellow Foxtail 8 8 1t) Harnyardgrass 9 l t) l (l ll) (rabgrass 9 ll) Ill ll) (heatgrass l ltl i Morning (ilor 9 It) Hi It) Hindweed 4 H I claim:

I. A compound of the formula l N N O 7.'('-R" ll ll ll l R'-C\ /(N('N-((H ),,C'H (CH- 1 l S R R 7.-'-( R wherein R is selected from the group consisting of lower alkyl. lower alkenyl. lower chloroalkyl. lower bromoalkyl. trifluoromcthyl. cycloalkyl of from 3 to 7 carbon atoms. lower alkoxy. lower alkylthio. lower alkysulfonyl and lower alkylsulfinyl; Z and Z are independently selected from the group consisting of oxygen and sulfur; R", R. R. R". R" and R are each selected from the group consisting of hydrogen and lower alkyl. m is an integer from 0 to 2. and n is the integer l or 2.

2. The compound of claim I, N-[Z-trifluoromethyll.3.4-thiadiazol5yl)'N'-( l.3 dioxolan-l-ylmethyl N'-methylurea.

3. The compound of claim I, N-[2-t-butyl-l,3 4- thiadiazol 5 yl)-N'-( l,3-dioxolan-2-ylmethy])-N'- ethylurea.

4. The compound the claim I, N-(Z-methylthiol.3.4-thiadiazol-5-yl )-N-methyl-N l .3-dithiepan 2- ylmethyl N-methylurea.

5. The compound of claim 1, N-(Z-methylsulfonyll.3.4-thiadiazol-Syl)-N-methyl-N-(1.3-dioxan-2- ylmethyllurea.

6. The compound of claim 1, N-(2-isopropyll.3.4- thiadiazol-Syl )-N-ethyl-N-( 4-methyl-l .3-dioxolan-2- UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,901,902

DATED August 26, 1975 Page 1 of 3 INVENTORQO 1 John Krenzer It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below,

column 1, line 18 for "consistof" read consisting of column 3, line 11, for "vene" read uene column 3, line 23, for "methylpropadioll,2, read methylpropandiol-l,2,

column 3, line 29, for "pentadithioll,2," read pentandithi0ll,2,

column 3, line 39, for "2amino5- '-chlopropyll,3,4" read 2-amino-5-7-chloropropyl-l,3,4-

column 4, line 38, read for "emempli" exemplicolumn 5, line 20, for "fof" read for column 5, line 33, for "2-Trifluormethyll,3,4-thiadiazol- 5-yl" read 2-Trifluoromethyll,3,4-thiadiazol-5-yl column 6, line 32, for "abd" read and column 6, line 60, for "2-chloromethyl-l,3-dithiepan" read 2-chloromethyl-l,3-dithiepane column 7, line 53, for "N-(l,3-Dioxan-ylmethyl)amine" read N (l,3Dioxan2ylmethyl) amine column 8 delete line 6, "2methylsulfonyl-S-methylcarbamoyl chloride".

column 8, line 52, for "2methyloxy-5-amino" read 2- methoxy-S-amino- UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,901,902 DATED August 26, 1975 Page 2 of 3 lNvENTOR(O/: John Krenzer \t is certrfred that error appears rn the above-identified patent and that sard Letters Patent are hereby corrected as shown below:

column 8, line 53, for "N-(2methoxyl-l,3,4" read (2methoxy-l,3,4

column 8, line 62, for "thiadiazol-S-yl)N'(4-ethyll,3 dioxolan3ylmethyl)" read thiadiazol-5yl)-N'(4 ethyl-l,3-dioxolan-2-ylmethyl) column 8, line 67, and column 9, lines 1 and 2, for "1,3,4-

thiadiazole phosgene N-(2-cyclohexyl-l,3,4thiadiazol S-yl)N'(4ethyl-l,3dioxolan3ylmethyl)N'propylurea." read N-(2-allyl-l,3,4-thiadiazol-5-yl)N-ethyl-N (l,3-dithiolan-2-ylmethyl)N'-methylurea.

column 10, line 13, for "thiadiazol-S-yl)NhexyN'-(4,5

dimethyll,3" read thiadiazol-S-yl)Nhexyl-N'(4,5 dimethyll,3

column 10, line 30, for "compounds" read compound column 10, line 50, for "suffieiently" read sufficiently column 11, line 12, for "ingreedients" read ingredients 24, delete "The concentration of the invention."

column 11, lines 23 and new compounds of this herbicidal column 11, line 42, for "herbicital" read column 11, line 62, for "cloroxu" read chloroxucolumn 12, line 4, for "8(chloroacetyl)" read l-(chloroacetyl) UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 1 3,901,902

DATED I August 26, 1975 Page 3 of 3 INVENTORQO i John Krenzer it is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In column 12, line 29, for "difulfide" read disulfide In column 12, line 29, for sindome" read sindone In Claim 4, column 14, line 40, for "The compound the claim 1,"

read The compound of claim 1 Signed and Scaled this Tenth Day of August 1976 sent Arrest:

RUTH C. MASON C. MARSHALL DANN AMP-fling Offle" Commissioner of Patents and Trademarks 

1. A COMPOUND OF THE FORMULA
 2. The compound of claim 1, N-(2-trifluoromethyl-1,3,4-thiadiazol-5-yl)-N''-(1,3-dioxolan-2-ylmethyl)-N'' -methylurea.
 3. The compound of claim 1, N-(2-t-butyl-1,3,4-thiadiazol-5-yl)-N''-(1,3-dioxolan-2-ylmethyl)-N'' -ethylurea.
 4. The compound the claim 1, N-(2-methylthio-1,3,4-thiadiazol-5-yl)-N-methyl-N''-(1,3-dithiepan-2 -ylmethyl)-N''-methylurea.
 5. The compound of claim 1, N-(2-methylsulfonyl-1,3,4-thiadiazol-5-yl)-N-methyl-N''-(1,3-dioxan-2 -ylmethyl)urea.
 6. The compound of claim 1, N-(2-isopropyl-1,3,4-thiadiazol-5-yl)-N-ethyl-N''-(4-methyl-1,3-dioxolan-2 -ylmethyl)urea. 